Cave slimes are Slayer monsters that require level 17 Slayer to kill. They inflict poison regardless of whether they do damage or not, so it is advised that the player brings a form of anti-poison when fighting them. As they are located in the Lumbridge Swamp Caves, a rope is needed if you have not entered the dungeon before. A light source is also required, but be aware that any exposed light sources (such as a candle) may explode, causing some damage.

Cave slime are found in two rooms of the caves. Open light sources will flare brightly, and ignite gas in the northern room, but the entire southern room is risk free. For either room you will have to pass by a Wall beast, so head protection (Spiny helmet/Slayer helmet) can be helpful to avoid damage.